Technical Field
The present invention relates to a printing system, a printing apparatus and a printing method.
Description of the Background Art
A silk screen method or the like is widely used in the past as a method of performing textile printing on fabric. In textile printing by a silk screen method or the like, a plate in which a hole through which dye passes is formed in an area to be dyed in fabric is prepared in advance, and dyeing is performed using the plate.
In addition, an inkjet printer for performing printing by an inkjet method is used widely in the past, which is illustrated in http://www.mimaki.co.jp (Non-Patent Document 1). Furthermore, in recent years, it is considered to use an inkjet printer for various applications. It is also considered to perform textile printing on fabric by performing printing on a medium of fabric through the usage of ink for textile printing, for example.
When textile printing on fabric is performed by an inkjet printer, it is thought that dyeing of various designs can be performed efficiently because there is no necessity to prepare a plate in advance. However, through extensive research, the inventor of the present application found that it might be difficult to achieve, by merely using an inkjet printer having a traditional configuration, the equivalent quality to that of the case of dyeing in the conventional manner through a silk screen method and the like. Further, through extensive research, the inventor of the present application also found that the cause of such a problem is related to the principle that color printing is performed in an inkjet printer.
More specifically, for example, in an inkjet printer, color printing is usually performed by using respective colors of inks: Y, M, C and K. Therefore, when color printing is performed by an inkjet printer, the amount of ink to adhere to each position of a medium would be different depending on color or density to be represented. As a result, when printing is performed on a medium of fabric by an inkjet method, ink penetrates the fabric from a print surface to the shallow position in some areas, and ink penetrates even to the back side of the print surface in other areas, depending on color or density to be printed. In this case, in the back surface of the medium, in some areas where the print surface is pale in color, the original color of the fabric (e.g. white) is presented, and in other areas where the print surface is deep in color, the color of the print surface reaches to the back surface thereof.
As a result, for example, an impression is made that the printing is mottled when the back surface of the medium is seen after printing. In addition, since the amount of ink changes depending on color and density as described above, only one surface (printing surface) of the fabric can be dyed sufficiently.
Further, when color printing is performed by Y, M, C, K inks, if errors or variations occur in the discharge amount from the inkjet heads for each color, color blurring would occur. Furthermore, even if correction is performed on variations due to individual differences of the inkjet heads, it is difficult to avoid color blurring caused by malfunction or an error during the operation.
In addition, a medium of fabric may be washed after printing. When the medium is washed, some fibers (yarn) may move in the fabric. As a result, in an area where the amount of adhering ink is small, fibers where ink does not adhere may move, and the original color (white) of the fabric may appear on the front surface. Therefore, when printing is performed on a medium of fabric by an inkjet method, if an inkjet printer having a traditional configuration is used, wash fastness may become insufficient.
In order to sufficiently penetrate ink to the back surface of the fabric, for example, the overall amount of the ink to be discharged to the medium might be increased, so that the sufficient amount of ink adheres to an area which is pale in color. However, in order to perform color printing by using Y, M, C, K inks, typically, it is necessary to discharge ink droplets of different color inks to neighboring or overlapping positions. In this case, when the amount of ink to be discharged is increased, it takes a long time to be dried on the medium, and bleeding between inks of different colors is likely to occur. As a result, proper printing becomes difficult. Therefore, when printing is performed on a medium of fabric using Y, M, C, K inks, it is not easy to increase the amount of ink. Thus, an object of the present invention is to provide a printing apparatus and a printing method capable of solving the problems.